Saturday, July 30, 2011

The Inner Geek here with another installment of my Reaver Titan project.

As I was trimming and preparing the pieces of the Reaver Titans' legs I thought I would share some tips on working with resin. Of course, the first tip is always safety, never inhale the dust from sanding or grinding this stuff! Next we have the washing which I covered in detail in an earlier post. The following are just a couple more tips in regards to trimming the pieces...

Mold lines. They suck. That's not the tip, just a fact. On resin pieces we want to trim the piece so that there is no line. Easy enough if it is a traditional plastic type of mold line where the piece is one uniform level with the line protruding out from it. But what about when the piece is not uniform and the line is the result of an uneven cast? We still need to get the pieces to match up while trimming the least amount possible. Here is an example of such a mold line.

This a trick I use to help ensure that I trim just enough. I take a sharpie marker and make trace over the line. Make a couple of passes if needed, but get the whole mold line black.

Now you can begin to trim along the mold line. You may use a file or a hobby knife, whichever you are comfortable with. Where the part doesn't need much trimming, the marker will come off quickly. Where marker remains, the part is not even, or flush.

Concentrating on areas where the marker remains, you will see less and less marker as the two sides of the part become more flush. Use common sense here, you may have to trim down areas where the marker has already disappeared to reach the parts where it has not. The idea is to use the marker to help you see where there is more trimming to be done and where the part is already even. The line will eventually disappear completely, but it is not always necessary to go that far. This much marker is acceptable to me for this particular part.

Another thing to remember about resin, it cuts a little funny when you use clippers. Sometimes where the vents (the extra sprue bits colored black below) are you can cut too close and break off a bit of the actual piece. I believe this happens because the resin tends to be weaker in these areas. So, when trimming these large bits I recommend clippers. But, I also recommend trimming different ways according to where vent is located. On a vent like the one below, where the vent is on surface you will see when finished, you do not want to have your clippers flush with the piece. I would leave some space between the clippers and the edge of the piece, then trim the remainder with a knife or file.

For the next piece, you may notice that the vents are on surface I've designated with marker. This surface will be hidden as it's the inside of a joint. The hip joint to be exact. I will put the clippers right against the piece in a situation like this. If a small indention results from the close cut it will never show.

I hope you've enjoyed this quick trip to resin land. I'm sure as this project moves forward there will be more tips and tricks that pop up and I'll be happy to share them all with you. Now I'm just trying to think of a way to stick the legs together to do mock ups for positioning. Some sort of super blu tac may be in order!

Thanks for stopping by. If you have any questions, comments, suggestions, or entertaining insults, by all means leave me a comment!